Add files via upload
This commit is contained in:
parent
08d803c625
commit
db0e296813
1 changed files with 83 additions and 0 deletions
|
@ -0,0 +1,83 @@
|
|||
/* Copyright 2020 Frank Adams
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
// This software interfaces the Teensy 3.2 with a laptop pointing stick (aka trackpoint) that is not PS/2.
|
||||
// Raw trackpoints use 4 resistive strain gauges for the left, right, up, and down detection.
|
||||
// The connections from the Teensy are 3.3 volts, ground, x voltage to A0, and y voltage to A1.
|
||||
// In the Arduino IDE, select Tools, Teensy 3.2. Also under Tools, select Keyboard+Mouse+Joystick
|
||||
//
|
||||
// Revision History
|
||||
// Rev 1.0 - March 28, 2020 - Original Release
|
||||
// Rev 2.0 - May 29, 2020 - Changed dead zone methodology
|
||||
//
|
||||
// declare and initialize variables
|
||||
int x_read; // stores the reading from the X ADC
|
||||
int y_read; // same for the Y ADC
|
||||
char mx; // signed byte used by the Mouse.move function for x value. Positive value moves to the right
|
||||
char my; // positive y value moves down
|
||||
int x_delta; // signed 16 bit value gives x movement amount
|
||||
int y_delta; // y version.
|
||||
int x_center; //resting position of x sensor
|
||||
int y_center; //resting position of y sensor
|
||||
int noise_zone = 175; // dead zone around the center. Increase this number if
|
||||
// the cursor moves without touching the TP. Decrease if
|
||||
// too much force is needed to move the cursor.
|
||||
|
||||
void setup()
|
||||
{
|
||||
delay(1000); // delay a second to let things settle out
|
||||
analogReadRes(13); // set ADC resolution to 13 bits (16 bit ADC but low 3 bits are random noise)
|
||||
analogReadAveraging(8); // ADC will take the average of 8 reads
|
||||
x_center = analogRead(A0); // store the center (no movement) position for x
|
||||
y_center = analogRead(A1); // same for y.
|
||||
// When the keyboard code is added, detect when Fn - F8 is pushed to indicate that
|
||||
// x_center and y_center should be read again from the ADC. This would be because
|
||||
// the operator notices the cursor is moving without being pushed.
|
||||
}
|
||||
//
|
||||
// ************************************Main Loop***************************************************************
|
||||
void loop() {
|
||||
mx = 0; // for each loop, start with zero and update only if movement detected
|
||||
my = 0; // same for y
|
||||
//
|
||||
x_read = analogRead(A0); // read the ADC tied to the X sensor
|
||||
y_read = analogRead(A1); // read the ADC tied to the Y sensor
|
||||
// Check if X or Y movement is beyond the dead zone
|
||||
if ((x_read > (x_center + noise_zone)) || (x_read < (x_center - noise_zone)) || (y_read > (y_center + noise_zone)) || (y_read < (y_center - noise_zone))) {
|
||||
// Only do the following if at least one reading is beyond the dead zone.
|
||||
// Figure out if the X value is to the right or the left of the center resting value
|
||||
if (x_read > x_center) { // is X ADC to the right of the resting position?
|
||||
x_delta = (x_read - x_center) / 10; // find out how far beyond center. Divide by 10 to slow it down.
|
||||
mx = byte(x_delta); // convert signed 16 bit to signed 8 bit
|
||||
}
|
||||
else { // X ADC is equal or to the left of the resting position
|
||||
x_delta = ((x_center - x_read) / 10) * -1; // Answer should be negative so multiply by -1
|
||||
mx = byte(x_delta); // convert signed 16 bit to signed 8 bit
|
||||
}
|
||||
// Figure out if the Y value is above or below the center resting value
|
||||
if (y_read > y_center) { // is Y ADC above the resting position?
|
||||
y_delta = ((y_read - y_center) / 10) * -1; // up movement is negative for Mouse.move function
|
||||
my = byte(y_delta); // convert signed 16 bit to signed 8 bit
|
||||
}
|
||||
else { // Y ADC is equal or below the resting position
|
||||
y_delta = ((y_center - y_read) / 10);
|
||||
my = byte(y_delta); // convert signed 16 bit to signed 8 bit
|
||||
}
|
||||
}
|
||||
// send the x and y data over usb if either one is not at center position
|
||||
if ((mx != 0x00) || (my != 0x00)) {
|
||||
Mouse.move(mx,my);
|
||||
}
|
||||
//
|
||||
// **************************************End of trackpoint routine***********************************
|
||||
//
|
||||
delay(30); // wait 30ms before repeating next polling cycle
|
||||
}
|
Loading…
Reference in a new issue